Improvement in extracting oil from pigs  feet



UNITED STATES PATENT OFFICE.

CHRISTIAN WAHL, OF CHICAGO, ILLINOIS.

IMPROVEMENT IN EXTRACTING OII 'FROM PIGS FEET.

Specification forming part of Letters Patent N0. 36,184, dated August 12, 1862.

To all whom it may concern.-

Be it known that I, CHRISTIAN WAHL, of Chicago, in the county of Cook and State of Illinois, have invented a new and improved process for treating pigs feet to extract their contained oil and gelatinous matter; and I do hereby declare that the followingis a full and exact description of the same.

The process at present employed for extracting the oil and glue from pigs feet is to boil or steam them, which process is subject to the objections that the oil as well as the gelatinous matter contained in them (employed in the manufacture of glue) is deteriorated in quality and value.

My invention is intended to obviate and remedy thesedefects; and it consists in subjecting the feet to an intense pressure in a hydraulic or other powerful press to extract from them all their contained oil, and then to take the product left in the press (the skin, bone, and muscles,) and subjectit to the liming process ordinarily employed in the manufacture of glue, and well understood by adepts, after which it is subjected to a boiling process for a sufficient length of time to extract from itvits contained gelatine for the purpose of making the same into glue by the ordinary and wellknown process.

The pigs feet are first to be placed in proper receptacles in a hydraulic or other powerful press, (the former preferred,) and are subjected to such a degree of pressure as will press out and abstract from them all the oil contained in them, which oil is of the nature of the m arketable article known as neats-foot oil. The resultant product left in the press is then treated like any other material from which glue is made in the ordinary and well-known manner. After extracting the gelatinous matter or glue the principal residuum (the bones of the feet) may then be ground into b0ne-dust for manuriug purposes, if required.

The process will be expedited and facilitated by subjecting them (before being submitted to the pressure above described) to a steam or other artificial heat of aboutl50 which should becontinued for a sufficient length of timesay about thirty minutes-to soften them, so that their contained oil may be more readily extracted by the pressure to which they are to be subjected.

What I claim as my invention, and desire to secure by Letters Patent, is-

The process for treating pigs feet for the extraction of their contained oil and gelatinous matter, as herein set forth and described.

CHRISTIAN WAHL. 

